It's creepy because he was making unwanted sexual solicitation of a complete stranger. If he has zero moral compass in that situation, what other inappropriate things might he do when around children? He's a creep.

He was being lewd and disrespectful to a woman minding her own business in her own car. Creep. He's probably the type who hits on the early-developed 13 year old girl and then claims "jail bait" like a FUCKING CREEP.